In conventional gas insulated switchgears, there is a gas insulated switchgear mainly composed of three circuits, which is referred to as a ring main unit for distribution and collection of electrical energy. For example, if the gas insulated switchgear is designed for distribution, each circuit of the three circuits is used for the purpose of drawing-in from the outside, drawing-out to the outside, and electric power supply to distribution destinations.
With the aim of function integration and size reduction of gas insulated switchgear, there is a gas insulated switchgear that integrates switches and connection destinations of three circuits. Furthermore, in order to flexibly cope with apparatuses and the number of circuits which constitute the circuits, there also exist ways in which a gas insulated switchgear is configured in a unit of one board including one circuit or two circuits and these gas insulated switchgears are combined.